How to make an enemy 2d chasing player?

I 'm doing a 2d platform game , I need to make enemies but do not know how.
the enemy shall patrol and chase the player only when the player enters in the trigger of the enemy. i’d need a script because i am noob in c#. Sorry if I have not written correctly but i’m Italian. Thank you in advance. Please, is pretty urgent!

It sounds like you are struggling with the basics. I would suggest watching this tutorial series. Just posting code would complicate things. It would be beneficial for you to learn! 14. 2D Platformer - ENEMY AI 1/3 - Unity Tutorial - YouTube